After being so disappointed with the previous book of the series I am so pleased to be able to say this book, number 4 of the "Rogue Hearts" series, is wonderful. The "Author's Notes" at the back of the book explains that the plot is based on a real plot that happened in 1820 and it rings with realism. All of the books have been the story of how one of the Amesbury brothers find the love of their life. This one is about the final brother, Grant. In previous books he has been the almost black sheep of the family. He is cold, avoids social situations, came home from the war with a horrible scar from his eye to the bottom of his cheek, and is hostile toward the thought of women, romance, and marriage. If he says anything it is usually a one or two word statement and he glares so much most people find him intimidating. There are rumors that he works for Bow Street but no one can get close enough to him to know for sure. In book 2 he is instrumental in saving one of his brother's life when he is hung, in book 3 he saves the life of his youngest brother by shooting the bad guy between the eyes, and we know he was a sharpshooter in the Army.He is indeed working on a project for Bow Street. The head of the organization has asked him to help determine the validity of rumors they have heard about a possible assassination attempt on the Prime Minister. Since Grant is the brother of an earl he is asked to infiltrate the upper crust friends and advisors of a man who hopes to become the next Prime Minister to see if he is really involved in a conspiracy. Grant hates the thought of participating in society events but if it for an investigation he will do it to ensure the safety of England. While doing so he meets the suspects daughter and finds himself attracted to her. He is determined to not let her charms distract him from his job, because "all women are snakes just trying to get their fangs into any unsuspecting man". He has walled off his heart and he will never allow another woman to trick him again. What other woman? Did he allow a woman into his heart only to have it broken? Does he hate all women because of that one? Hmmmmm,,,,Meanwhile, Jocelyn Fairley, daughter of the suspect, has had three seasons with no interest except two men; one a fortune hunter and the other not approved of by her father. She has decided not to participate in this season in hopes she can help her father with his political career. She will host parties and dinners for her father so he can become the next Prime Minister. She is relentlessly cheerful, smiles all the time, considers herself a little too plump, and if after one more season next year she doesn't find a husband she will make a happy life for herself as a spinster. She is so kind hearted she can't help take care of people in need and tries to rescue anyone she has to power to help. Will she be the one to rescue Grant from his past? Can she ever convince Grant that he can trust her not to break his heart if he opens it to her? She is very determined to love Grant until his brokenness is healed. She might be the one who can do it; we will just have to keep reading to see if it happens.This book is very well written, no major typos that I remember, maybe use of foul language once but not really that bad, and the story is logical with no major plot holes. All in all, a great book and very worth the read.